Figure 1-15
USG9580 switching network
The level-1 switching chip on one LPU is fully connected to the level-2 switching chips on
the SFUs. The level-2 switching chips on the SFUs are also fully connected to the level-3
switching chip on another LPU. In addition, the level-2 crossbar switching chips work in load
balancing mode on multiple switching planes. The entire switching network is unblocked. The
process of transmitting data packets across the switching network is as follows:
1.
Data packets enter an LPU through physical interfaces and are fragmented into cells of a
fixed length. These cells are then sent to the level-1 switching chips. After being
buffered and scheduled, the cells enter the crossbar switching chips on the SFU. The
level-1 switching chip on an LPU is fully connected with all of the level-2 switching
chips. As a result, the same number of cells can be distributed to each level-2 switching
plane. This implements load balancing on switching planes and facilitates fault tolerance.
2.
After the cells reach the crossbar switching chips, the crossbar switching chips schedule
the cells to the corresponding outbound interfaces according to the destination interfaces
of the data packets. The cells are then sent to the level-3 switching chips on another
LPU. The switching of cells by the level-2 switching chips is then completed.
3.
After the cells reach the level-3 switching chips on another LPU, the system searches for
the destination interfaces. Once found, the cells are reassembled and sent out through
physical interfaces, completing the switching of the data packets.
1.1.7 Control Plane
This section describes the functions and features of the control plane.
USG9580 uses the MPU (EKEX16-FWCD00MPUB00) to implement the control plane
functions. For details about the MPU, see
functions of the MPU are described from the aspects of system control and management,
system maintenance, and reliability.
System Control and Management Unit
As the system control and management unit, the MPU provides the following functions on the
system control panel:
HUAWEI USG9500 Series
Hardware Guide
1 Hardware Overview
Issue 03 (2017-12-15)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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